I am attempting to increase the PIO bus speed from 33 to 66 and to turn on DMA using ATA/EIDE drives. I used to be able to do this with the idebus setting and the hdparm command. So far I have not been able to achieve this I get: [root@aultlinux3 ~]# hdparm -X66 -d1 -u1 -m16 -c3 /dev/hdd /dev/hdd: setting 32-bit IO_support flag to 3 setting multcount to 16 setting unmaskirq to 1 (on) setting using_dma to 1 (on) HDIO_SET_DMA failed: Operation not permitted setting xfermode to 66 (UltraDMA mode2) multcount = 16 (on) IO_support = 3 (32-bit w/sync) unmaskirq = 1 (on) using_dma = 0 (off) When I try. I have also tried adding the options lines for the various drivers (ide1, ata_piix, libata) but it seems to have no affect. Anyone been able to set up DMA for ATA/EIDE drives or to set the bus speed in RedHat 3.0 release 4? On older, slower drives I was able to get speed up to 14.92 mb/sec using these methods, on these newer, faster drives I can only get to 5.1 mb/sec On Old RedHat: [root@aultlinux2 root]# hdparm -m16 -c3 -X mdma2 -d1 -a8 -u1 /dev/hdb /dev/hdb: setting fs readahead to 8 setting 32-bit IO_support flag to 3 setting multcount to 16 setting unmaskirq to 1 (on) setting using_dma to 1 (on) setting xfermode to 34 (multiword DMA mode2) multcount = 16 (on) IO_support = 3 (32-bit w/sync) unmaskirq = 1 (on) using_dma = 1 (on) readahead = 8 (on) [root@aultlinux2 root]# hdparm -Tt /dev/hdb /dev/hdb: Timing buffer-cache reads: 128 MB in 1.56 seconds = 82.05 MB/sec Timing buffered disk reads: 64 MB in 4.29 seconds = 14.92 MB/sec On New improved RedHat with newer, faster drives: [root@aultlinux3 ~]# hdparm -X66 -d1 -u1 -m16 -c3 /dev/hdd /dev/hdd: setting 32-bit IO_support flag to 3 setting multcount to 16 setting unmaskirq to 1 (on) setting using_dma to 1 (on) HDIO_SET_DMA failed: Operation not permitted setting xfermode to 66 (UltraDMA mode2) multcount = 16 (on) IO_support = 3 (32-bit w/sync) unmaskirq = 1 (on) using_dma = 0 (off) [root@aultlinux3 ~]# hdparm -tT /dev/hdc /dev/hdc: Timing cached reads: 3820 MB in 2.00 seconds = 1909.34 MB/sec Timing buffered disk reads: 16 MB in 3.11 seconds = 5.15 MB/sec This is using the SATA drive (can't set it using hdparm) as the boot drive with two EIDE drives chained off of IDE1, the EIDE drives are where I want to set it. So far the only light is rebuilding the kernel to support DMA as it seems the RedHat folks in their wisdom decided we really didn't want DMA support in the IDE interface as a default.imagine that, actually wanting the best performance. However, I haven't had much luck with rebuilding the kernel for firewire (read no luck at all) and had to download a prebuilt kernel with firewire enabled in order to use it (not this server). If no one has any ideas, how about a pointer to a prebuilt kernel rpm with DMA turned on? Thanks. Mike -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
